Optical and electronic properties of passivated InP(001) surfaces

The effect of chemical passivation in solutions of ammonium sulfide (NH$_4$)$_4$2S on the optical and electronic properties of the $n$-InP (001) surface has been studied. It has been shown that treatment in a 4% aqueous solution of (NH$_4$)$_2$S leads to a decrease of surface band bending and localized charges in near-surface region in the 2 times. Processing in a 4% alcoholic solution of (NH$_4$)$_2$S leads to a decrease in these parameters in 3 times, and moreover, the barrier photovoltage and also reduces in three times.